Ethanolamines, individually and in combination have many uses in the chemical industries. For example, ethanolamines can be used as corrosion inhibitors, lubricants and scouring agents for gas sweetening, detergents and specialty cleaners, concrete admixtures, flexible urethane foam catalysts, personal care products, photographic emulsions, solvents, dyes intermediates, rubber accelerator, emulsifiers, ink additives, oil additives, alkalization of water in steam cycles of power plants and nuclear plants with pressurized water reactors, pesticides and pharmaceutical intermediates, natural gas is also used as acid gas absorption solvent. Ethanolamines may also be used in the semiconductor field for wafer cleaning and photoresist striping applications because of their surfactant properties. Global demand for ethanolamines is increasing, and is projected to exceed 1.605 million tons by 2015.
Ethanolamines are flammable, corrosive, colorless, viscous liquids that are produced by the reaction of ammonia (NH3) and halohydrins or ethylene oxide (C2H4O) (EO). EO, however, is more widely used for commercial processes. To produce ethanolamines commercially, aqueous ammonia and ethylene oxide are contacted in a single stage or multi stage reaction chamber at a temperature of 50° C. to 257° C. There are three types of ethanolamines: MEA (H2NCH2CH2OH); Diethanolamine (HN(CH2CH2OH)2), also referred to as DEA; and Triethanolamine (N(CH2CH2OH)3), also referred to as TEA. The formation of MEA, DEA or TEA depends on whether an ammonia molecule reacts with 1, 2 or 3 EO molecules. The reactions have a parallel consecutive mechanism, so that the three products (MEA, DEA and TEA) are obtained simultaneously. Water is used as a catalyst in ethanolamine reactions.
Due to the demand for TEA in the petrochemical industry, needs exist for producing clear and colorless TEA with the slightest possible discoloration, e.g. measured as American Public Health Association (APHA) or Gardner color number, which retains these properties even over prolonged storage periods.